Requirements for upgrading MES versions

Observe the following requirements when upgrading MES:

• You cannot upgrade to the current version of MES from a version older than 3.5. To upgrade from a version older than 3.5 to the current version, you must first uninstall the previous version, and then install the new version.

• If you are upgrading from version 3.5 or older, it is recommended that you change all passwords, since the encryption scheme used in the older versions is not as secure as the newer encryption scheme.

• If your organization is using MES with System Platform, System Platform 2023 R2 SP1 Patch 2 is required. If the system has a previous version installed, it must be upgraded to System Platform 2023 R2 SP1 Patch 2 prior to installing MES.

• If your organization is using MES .NET controls in System Platform, you have to first remove the previous version of the MES .NET controls before upgrading to the current version of the controls. For the procedure, see Upgrade MES .NET controls for AVEVA InTouch HMI applications.

• Any deployed System Platform client controls using MES (for example, MES application objects, API scripting, .NET controls) should be undeployed from the node prior to upgrading.

• Prior versions of MES, including MES 2023, may install the AVEVA Single Sign-On Service.ASBServiceRepository feature from AVEVA Platform Common Services (PCS). To ensure compatibility, you must remove the Service Repository feature either before or after you upgrade MES. Before doing so, make sure that no other products require this feature. You can remove the Service Repository feature using the Windows Add Remove Programs utility for the PCS product.